Arnold Schwarzenegger made a rare political appearance on Monday in Sacramento to promote California's fight against climate change and to unveil his official portrait as governor.

Three years after leaving office, the Republican was attending a climate symposium with current Democratic Gov. Jerry Brown.

"While the politicians in Washington can't get anything done because of being stuck in these ideological foxholes, we here in California have two governors from two different parties, together in the same room fighting for the same green energy future," Schwarzenegger, a Republican, said at the summit.

Organizers are using the state's policies on the issue to prompt further action ahead of United Nations climate-change conferences in Peru and Paris.

"Countries and regions need to learn from the many successful initiatives pioneered in California and elsewhere," Secretary-General Ban Ki-moon wrote in a welcome message to those at the meeting in Sacramento.

During his tenure, Schwarzenegger signed California's landmark 2006 global-warming law, called AB32, which paved the way for the state's cap-and-trade system for controlling greenhouse-gas emissions by the worst polluters.

The gathering on Monday was held at a 250-seat auditorium at the headquarters of the California Environmental Protection Agency. It will feature research experts, businesses executives from Apple Inc. and UPS Inc., as well as actor-activist Ed Begley Jr.

Topics will include the costs of failing to move away from fossil fuels and cite noticeable changes such as the expansion of California's wildfire season.

Schwarzenegger will then head to the Capitol rotunda to unveil his portrait by an artist who has yet to be named. It will eventually hang on the third floor of the building next to the portrait of his recalled predecessor, Gray Davis.

As governor, Schwarzenegger had promised to bring fiscal accountability, but the state was facing a huge budget deficit when he left office. Brown has been credited with passing a tax increase, cutting services and bringing the budget back in balance.

In one of his final acts in office, Schwarzenegger commuted the involuntary-manslaughter sentence of the son of a former political ally.

Months after he left office, embarrassing revelations broke about an affair Schwarzenegger had with his maid that resulted in a son born out of wedlock. The disclosure devastated his marriage to Maria Shriver.

Since then, Schwarzenegger has largely committed to a Hollywood comeback. He appeared in this summer's "The Expendables 3," and returns to his cyborg assassin character in a new "Terminator" film due out next year.

Schwarzenegger previously told The Associated Press that he has no plans to run for elected office again.